The antimicrobial effect of various metals and their salts have been known for centuries. Their germicidal effects increased their value in utensils and as jewelry. The exact mechanism of the germicidal effect of silver is still not entirely understood, although theories exist. One of these is the “oligodynamic effect,” which qualitatively explains the effect on some microorganisms, but cannot explain antiviral effects. Silver is widely used in topical gels and impregnated into bandages because of its wide-spectrum antimicrobial activity.
Oligodynamic effects are demonstrated by other metals, specifically gold, silver, copper, zinc, and bismuth. Copper and copper alloys and compounds have long been used as a biostatic surface to line the bottoms of ships to protect against barnacles and mussels. Bacteria will not grow on a copper surface because it is biostatic. Copper alloys have become important netting materials in the aquaculture industry because they are antimicrobial and prevent biofouling and have strong structural and corrosion-resistant properties in marine environments. Organic compounds of copper are useful for preventing fouling of ships' hulls. Copper alloy touch surfaces have recently been investigated as antimicrobial surfaces in hospitals for decreasing the transmission of nosocomial infections.
Numerous scientific investigations have focused on the antimicrobial characteristics of the metallic copper and copper alloys, and have concluded that multiple mechanisms may be responsible for copper's antimicrobial effect, including increased production of reactive oxygen species such as singlet oxygen and hydroxide radicals, covalent binding of copper metal to reactive sites in enzymes and co-factors, interference with lipid bilayer transport proteins, and interaction of copper ions with moieties of microorganisms analogous to what have been proposed for silver ions.
The focus of the present invention is on low water solubility copper salts in wound care products such as wound closure products, wound dressings, lotions and gels, etc, wherein the compositions may be added to or incorporated in articles of manufacture which result in imparting these products antimicrobial properties. The materials of this invention have very high efficacy against a broad range of bacteria, viruses, molds and fungi, etc. These products include liquids and solids, wherein the solids include coatings.